1. Field of the Invention
The present invention relates to a pickup unit for use in a recording/reproducing apparatus for inserting and ejecting a recording medium to and from an entrance to perform recording and/or reproducing of information thereon.
2. Description of the Related Art
Recording/reproducing apparatuses, such as VTRs, CD players, CD-ROM changers are constructed so that a disc placed on a tray is inserted into the apparatus, and the disc is clamped and rotationally driven.
In general, in the CD-ROM changers, for example, a disc placement section and a mechanical section are provided inside a box-shaped casing, and a tray-type magazine is loaded in the disc placement section from an insertion slot.
In addition, in the CD-ROM changers, a tray selected from a plurality of trays in a magazine M loaded in the disc placement section is drawn out by a tray loading mechanism, the disc is clamped within a pickup unit provided in the mechanical section, and the disc is rotationally driven by a turntable of the pickup unit.
The pickup unit includes a pickup chassis having a spindle motor mounted thereon for use in picking up and rotating the disc, and a moving chassis having a disc clamper, a driving force transmission gear, and a DC motor serving as a drive source.
According to the above conventional art, however, if the DC motor is mounted on the moving chassis, the DC motor section is projected and prevents a reduction in thickness. Thus, the DC motor is mounted on the pickup chassis, and the driving force of the DC motor is transmitted to the driving force transmission gear provided on the side of the moving chassis through a gear.
When the pickup chassis and moving chassis are constructed in such a manner that they can be opened and closed around a rotary shaft, if the driving force transmission gear and the DC motor for driving the driving force transmission gear are provided on separate chassis as described above, the pickup chassis and the movable chassis are inclined between the DC motor and the driving force transmission gear. Therefore, a universal joint and so forth are required for the unit and the structure becomes complicated, so that not only the cost increases, but also transmission reliability of the driving force is unstable.